高级检索+

西藏高寒区抗冻型基材质量评价及植被修复效果

Evaluating frost-resistant substrate quality and the effects of vegetation restoration in the alpine region of Tibet, China

  • 摘要: 抗冻型基材是一种用于边坡生态修复的护坡土壤,定量评价抗冻型基材在西藏高寒区边坡植被修复中的实际应用效果,为高寒地区边坡生态修复提供参考和依据。通过连续5年实地取样和现场监测,测定了边坡植被修复后2019—2023年间抗冻型基材的物理、化学和生物学性质及植被修复情况,并与立地条件相似的植被混凝土和天然土修复情况进行了对比分析,结合主成分分析(principal component analysis,PCA)构建土壤质量指数(soil quality index,SQI),并采用回归分析探究土壤质量与植被影响关系。结果表明:相对于其他两种土壤,抗冻型基材在西藏高寒区的植被修复效果最好,理化生性质均有显著提升(P<0.05),土壤质量指数SQI均值(5a)从小到大依次为抗冻型基材(0.681)、植被混凝土(0.605)、天然土(0.378)。3种土壤质量SQI均值和植被修复效果均随时间呈抛物线型走势,在2020年左右达到最高值。PCA显示水稳定性大团聚体含量(water stable macroaggregate content,WAC)、黏聚力(soil cohesion,SC)、有机质(soil organic matter,SOM)和过氧化氢酶活性(catalase activity,CAT)为关键评价指标,权重占比较高。回归分析表明,SQI值与4种植被指标呈紧密正相关,SQI值可准确评价边坡生态修复效果。抗冻型基材在高寒区边坡植被修复应用中具有显著优势,该研究为高寒区边坡修复提供了有效的技术支持,并为后续基材在不同环境气候和边坡条件中的使用提供科学支撑。

     

    Abstract: Frost-resistant substrate is one type of soil suitable for the slope ecological restoration in alpine regions. It is composed of natural soil, cement, organic materials, greening additives, silicon powder, and palm fiber. This study aims to quantitatively evaluate the application of the frost-resistant substrate for the slope vegetation restoration in the alpine region of Tibet, China. Field sampling, field monitoring, and indoor experiments were conducted to explore the physical, chemical, and biological properties of the frost-resistant substrate. A systematic investigation was made to explore the slope vegetation restoration from 2019-2023. The vegetation, concrete, and natural soil were adopted under similar site conditions. Principal component analysis was carried out on the microscopic images of the three substrates. The soil quality index (SQI) was then calculated after five years of monitoring. The results revealed that the frost-resistant substrate shared significantly superior physical and chemical properties, compared with both vegetation concrete and natural soil (P<0.05). Their SQI values were ranked in the descending order of the frost-resistant substrate (0.681) > vegetation concrete (0.605) > natural soil (0.378). The cement and brown fiber improved the stability of the frost-resistant substrates. While its fertility was enhanced by the organic materials, silicon powder, and greening additives. In addition, the frost-resistant substrate also demonstrated the optimal performance in terms of the vegetation coverage, species diversity, as well as both aboveground and belowground biomass. An inverted "V" trend was observed in the SQI and vegetation restoration for the three types of soils, as the years increased. The highest value was reached in 2020. And then there was the gradual decrease. The freeze-thaw process reduced the physical and chemical properties of the soil. There was a smaller decrease in the SQI. There was a relatively minor impact of the freeze-thaw process on the frost-resistant substrate, compared with the three types of soil. The proportion of green additives and cement in the substrate material ratio further increased by 1%-2%, in order to improve the long-term use. Regression analysis showed that a close correlation was found between the SQI values and the four vegetation indicators. The SQI was accurately evaluated for the slope vegetation restoration. Principal component and correlation analysis reveal that the greatest contribution to the soil quality was found in the four indicators, including the water stable macroaggregate content (WAC), soil cohesion force (SC), soil organic matter (SOM), and catalase activity (CAT). The soil quality was evaluated and improved in different climate zones, parent rock types, and slopes in the future. The frost-resistant substrate was verified in the application of slope vegetation restoration in the alpine regions. A scientific basis was also offered to optimize the frost-resistant substrate ratio. Restoration effects were improved under different environmental conditions. The application scope of the sample plot was extended to include the monitoring time. The slope site conditions were combined after application. The applicability experiment was carried out to fully meet the long-term application of the frost-resistant substrate in the slope vegetation restoration. The finding can also provide a strong reference and effective technical support for the slope ecological restoration in alpine regions.

     

/

返回文章
返回